Represents a structure loaded from a URL (including a file URL)
A few custom query parameters are supported:
format=[pdb|cif] Specify the file format (will otherwise be
guessed from the extension)
pdbId=[String] Specify the PDB ID (also guessed from the filename)
chainID=[String] A single chain from the structure
residues=[String] Residue ranges, in a form understood by
SubstructureIdentifier